GXL extraction of avocado pulp solid residue: impact of operational variables on yield and recovery of bioactive compounds

• Grant number: 23/17485-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2024
• End date: February 28, 2025
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Engineering
• Principal Investigator: Juliane Viganó
• Grantee: Maria Eduarda Machado Soares
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil

Abstract

This project aims to develop an extraction method for reusing the solid by-product of avocado pulp oil extraction. Irrespective of the production scale, mitigating the generation of by-products poses a challenge in food processing. Concurrently, sustainable consumption and production is one of the seventeen sustainable development objectives outlined in the United Nations 2030 agenda. Thus, the reuse of by-products from the industrialization of avocado oil can contribute to reducing waste generation, fostering responsible industrial development. Simultaneously, the reuse process can catalyze the development of new products, adding value to underappreciated materials. Therefore, this project proposes the application of gas-expanded liquid extraction (GXL) to the solid residue of avocado pulp. The variables to be investigated include temperature (30-60 ºC), the composition of the solvent (ethanol:CO2 (m/m); 2:1, 1:1, and 1:2), and extraction time (5-120 min). These factors will be scrutinized for their effects on overall extraction yield, overall extract recovery, yield of phenolic compounds, carotenoids, antioxidant capacity, and residual protein content in the extraction by-product. The overall yield will be determined through gravimetry, while global extract recovery will be assessed by comparing the overall yield with the exhaustive extraction yield in a Soxhlet apparatus. The yield of phenolic compounds, carotenoids, and antioxidant capacity will be determined using spectrophotometric techniques. This project is expected to propose an extraction method by GXL whose variables result in the maximization of response variables, then proposing a method for obtaining bioactive compounds from the industrial byproduct.